CCl4 Injection Research Articles

Therapeutic Effects of an Inhibitor of Thioredoxin Reductase on Liver Fibrosis by Inhibiting the Transforming Growth Factor-β1/Smads Pathway.

Liver fibrosis is an important stage in the progression of liver injury into cirrhosis or even liver cancer. Hepatic stellate cells (HSCs) are induced by transforming growth factor-β1 (TGF-β1) to produce α-smooth muscle actin (α-SMA) and collagens in liver fibrosis. Butaselen (BS), which was previously synthesized by our group, is an organic selenium compound that exerts antioxidant and tumor cell apoptosis–promoting effects by inhibiting the thioredoxin (Trx)/thioredoxin reductase (TrxR) system. The aim of this study was to investigate the potential effects of BS on liver fibrosis and explore the underlying molecular mechanisms of its action. Liver fibrosis models were established using male BALB/c mice through intraperitoneal injection of CCl4. BS was administered orally once daily at a dose of 36, 90, or 180 mg/kg. Silymarin (Si), which is a drug used for patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis, was administered at a dose of 30 mg/kg per day as a control. The action mechanisms of BS against liver fibrosis progression were examined in HSCs. The study revealed that the activity and expression levels of TrxR were elevated in the mouse liver and serum after CCl4-induced liver fibrosis. Oral administration of BS relieved the pathological state of mice with liver fibrosis, showing significant therapeutic effects against liver fibrosis. Moreover, BS not only induced HSC apoptosis but also inhibited the production of α-SMA and collagens by HSCs by downregulating the TGF-β1 expression and blocking the TGF-β1/Smads pathway. The results of the study indicated that BS inhibited liver fibrosis by regulating the TGF-β1/Smads pathway.

Hepatoprotective effect of Spirulina platensis against carbon tetrachloride-induced liver injury in male rats.

Spirulina platensis (SP) is an edible Cyanobacterium with ethnomedicinal significance. This study aims at evaluating the beneficial effect of SP against carbon tetrachloride (CCl4)-induced liver toxicity in male rats. Rats received intraperitoneal injections of CCl4 (2 ml/kg body weight [b.w.] per every other day) for 40 days, alone or in combination with oral treatments of SP (400 mg/kg b.w. per day). SP attenuated haematological disturbances, serum liver markers, hepatic necrosis and inflammation, and dyslipidemia in CCl4-intoxicated rats. SP also reduced CCl4-induced oxidative stress by increasing the activities of antioxidant enzymes, such as glutathione peroxidase, superoxide dismutase and catalase and glutathione content, and inhibiting lipid peroxidation products and nitric oxide levels in the rat liver. Further investigations revealed that SP counteracted CCl4-induced increased hepatic levels of Ki-67 (a parameter of cell proliferation), interleukin-6, and tumour necrosis factor-alpha and cyclooxygenase-2 messenger RNA expression. Noticeably, the supplementation of SP restored the decrease of proapoptotic p53 protein levels in the liver of rats treated with CCl4. SP prevented liver damage in CCl4-treated rats via augmentation of antioxidant defense mechanisms and inhibition of inflammatory cytokines/mediators and antiproliferative effects.

Therapeutic potential of Ni(II) Schiff base complex on CCl4 toxicity

Carbon tetrachloride (CCl4) is a known ecological hazardous xenobiotic that could motivate hepatotoxicity. We aimed to examine, for the first time, the therapeutic potential of nickel(II) diacetyl monoxime-2-pyridyl hydrazone complex versus CCl4-induced hepatotoxicity in rats. We used six rat groups of ten animals each. The negative control, vehicle, normal rats injected i.p. with the complex (2.4 mg/kg/day), positive control rats injected i.p. with CCl4, and treated rats administered complex via injection at low and high concentrations of 1.2 and 2.4 mg/kg/day, respectively at the same time as CCl4 injection for short-term (3-weeks) and long-term (8-weeks) treatment. Intoxicated-rodents exhibited significant elevations in the liver index, hepatic serum markers, and oxidative stress with significant reductions in the hepatic, antioxidants, nucleic acids, and proteins. Complex co-treatment with CCl4 significantly suppressed the elevated liver enzyme activities, attenuated oxidative stress, reactivated antioxidant-system components, and amended the hepatic tissue injury. The complex high dose was more efficient than the low dose. Results of negative control were analogous to those of normal rats injected with the complex high dose. The histopathological analysis also supported the above findings. These results show that complex has good antioxidant and therapeutic properties, which can help in treating and preventing CCl4-induced hepatotoxicity.

Effects of blocking chemokine receptor CCR1 with BX471 in two models of fibrosis prevention and rescue in mice

BackgroundThe induction, progression and resolution of liver fibrosis are influenced by multiple chemokines. The inhibition of CCR1 signalling by a specific non-peptide inhibitor (BX471) reduces kidney fibrosis after unilateral ureteral obstruction via suppression of leukocyte recruitment in mice. However, it remains unclear whether selective CCR1 inhibition also affects hepatic fibrogenesis. Therefore we aimed to study the effect of this intervention on liver fibrosis in prevention (CCl4 administration) and rescue (ABCB4-deficient mice) mouse models. MethodsIn the prevention model, hepatic fibrosis was induced by repeated injections of CCl4. Additionally, the verum group was treated with subcutaneous injections of BX471, while controls received vehicle only. ABCB4 deficient mice (on the BALB/c-background) with sclerosing cholangitis and biliary fibrosis received BX471 or vehicle, respectively (rescue model). Liver histopathology was assessed after Sirius red staining of collagen, and hepatic collagen contents were measured. In addition, we performed gene expression analyses of fibrosis-related genes. ResultsBX471 injections were tolerated moderately well by all mice, and all mice developed hepatic fibrosis. Significant differences were neither observed in serum aminotransferase activities after 6 weeks of treatment between the two groups in the prevention nor in the rescue model. Interestingly, hepatic collagen contents were significantly higher in mice treated with BX471 in the prevention model as compared to controls but histological stages of liver sections did not differ. Of note, we observed only moderate effects on liver fibrosis in the ABCB4 knock-out model. ConclusionsOur data indicate that BX471 treatment did neither affect serum and tissue markers of liver injury and fibrosis in the CCl4 model and only moderately in the Abcb4-/- model of biliary fibrosis. The animal models indicate that treatment with BX471 alone is unlikely to exert major beneficial effects in chronic liver disease.

Staging Liver Fibrosis: Comparison of Native T1 Mapping, T2 Mapping, and T1ρ: An Experimental Study in Rats With Bile Duct Ligation and Carbon Tetrachloride at 11.7T MRI.

T1, T2, and T1ρ might be potential biomarkers for assessing liver fibrosis. However, few studies reported the value of them in different animal models. To investigate and compare the performances of T1, T2, and T1ρ for noninvasively staging liver fibrosis in bile duct ligation (BDL) or carbon tetrachloride (CCl4 ) model. Prospective animal model. Liver fibrosis was induced by BDL or injection of CCl4 in 120 rats. 11.7T, T1 mapping with 10 repetition times, T2 mapping with 32 echo times, and T1ρ with 10 spin-lock times. T1, T2, and T1ρ were measured and correlated with liver fibrosis stages, as well as the degree of inflammation, steatosis, iron deposition, and the expression of cytokeratin 19. The discriminative performance of T1, T2, and T1ρ for staging liver fibrosis was compared. One-way analysis of variance (ANOVA), Spearman's correlation analysis, factorial design ANOVA, and receiver operating characteristic curves (P < 0.05 was considered statistically significant). T1, T2, and T1ρ (BDL: rho=0.73, 0.85, 0.68; CCl4 : rho=0.80, 0.29, 0.61) were significantly correlated with liver fibrosis stages, while there was no significant difference in T2 among stage F0-F4 in the CCl4 model (P=0.204). The area under the curves (AUCs) range of T1, T2, and T1ρ for predicting ≥F1, ≥F2, ≥F3, and F4 were 0.76-0.95, 0.89-0.98, and 0.80-0.94 in the CCl4 model. For the CCl4 model, the AUCs range of T1, T2, and T1ρ for predicting ≥F1, ≥F2, ≥F3, and F4 were 0.83-0.95, 0.61-0.74, and 0.73-0.89, respectively. T2 had significantly higher AUC in the BDL model than CCl4 model for diagnosing liver fibrosis. The most sensitive and accurate method for staging liver fibrosis appeared to be T1 in our animal models followed by T1ρ. T2 may not be suitable for evaluating liver fibrosis. 1 TECHNICAL EFFICACY STAGE: 2.

Assessment of liver injury using indocyanine green fluorescence imaging.

BackgroundTo investigate whether indocyanine green (ICG) fluorescence imaging can be used to evaluate chronic and acute liver injury induced by either a high-fat (HF) diet or carbon tetrachloride (CCl4).MethodsSprague-Dawley (SD) rats were randomly divided into three groups: control group, HF diet-induced model group, and CCl4-induced model group. The chronic and acute liver injury models were induced by a HF diet and intraperitoneal injection of CCl4, respectively. After HF feeding, the liver index, levels of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) of the rats were determined. The livers were also collected to evaluate histopathology damage by hematoxylin and eosin (H&E) staining. After in vitro perfusion of the liver and ICG administration, the liver fluorescence intensity and corresponding spectral value were measured by using real-image guided system (REAL-IGS).ResultsAfter HF feeding, the liver index and levels of serum ALT and AST were significantly increased, and the livers of the rats showed severe histopathological changes. Compared with the control group, the hepatic lobes of the model rats exhibited incomplete green fluorescence, and the corresponding spectral value was markedly reduced.ConclusionsICG fluorescence imaging can be used to evaluate liver injury induced by either a HF diet or CCl4.

Combined Effects of Amino Acids in Garlic and Buna-Shimeji (Hypsizygus marmoreus) on Suppression of CCl4-Induced Hepatic Injury in Rats.

The combination of the garlic-derived amino acid, S-allyl-l-cysteine sulfoxide (ACSO), and ornithine or arginine on CCl4-induced hepatic injury was examined. After investigating the effectiveness of the mixture of ACSO and ornithine or arginine in preventing hepatic injury in vivo, an extract rich in ACSO and ornithine was prepared by converting arginine in garlic to ornithine by arginase from Hypsizygus marmoreus (buna-shimeji), after screening the productivity of ornithine among 12 kinds of mushrooms. Co-administration of ACSO with ornithine or arginine suppressed the increase in aspartate transaminase, alanine transaminase, and thiobarbituric acid reactive substance, and the decrease in glutathione S-transferase and cytochrome p450 2E1 activities after CCl4 injection more effectively than a single administration of ACSO. All extracts prepared from garlic and buna-shimeji with low and high contents of ACSO and arginine or ornithine significantly suppressed CCl4-induced hepatic injury in rats. Considering that ACSO is tasteless, odourless, and enhances taste, and ornithine has a flat or sweet taste and masks bitterness, the extract rich in ACSO and ornithine from garlic and buna-shimeji could be considered a potential antioxidant food material that can be added to many kinds of food to prevent hepatic injury.

Inhibition of Oxidative Stress and ALOX12 and NF-κB Pathways Contribute to the Protective Effect of Baicalein on Carbon Tetrachloride-Induced Acute Liver Injury.

This study investigates the protective effect of baicalein on carbon tetrachloride (CCl4)-induced acute liver injury and the underlying molecular mechanisms. Mice were orally administrated baicalein at 25 and 100 mg/kg/day for 7 consecutive days or ferrostatin-1 (Fer-1) at 10 mg/kg was i.p. injected in mice at 2 and 24 h prior to CCl4 injection or the vehicle. Our results showed that baicalein or Fer-1 supplementation significantly attenuated CCl4 exposure-induced elevations of serum alanine aminotransferase and aspartate aminotransferase, and malondialdehyde levels in the liver tissues and unregulated glutathione levels. Baicalein treatment inhibited the nuclear factor kappa-B (NF-κB) pathway, activated the erythroid 2-related factor 2 (Nrf2)/heme oxygenase 1 (HO-1) pathway in liver tissues, and markedly improved CCl4-induced apoptosis, inflammation and ferroptosis in liver tissues exposed with CCl4. In vitro, baicalein treatment improved CCl4 -induced decreases of cell viabilities and knockdown of Nrf2 and arachidonate 12-lipoxygenase (ALOX12) genes partly abolished the protective effect of baicalein on CCl4 -induced cytotoxicity in HepG2 cells. In conclusion, our results reveal that baicalein supplementation ameliorates CCl4-induced acute liver injury in mice by upregulating the antioxidant defense pathways and downregulating oxidative stress, apoptosis, inflammation and ferroptosis, which involved the activation of Nrf2 pathway and the inhibition of ALOX12 and NF-κB pathways.

Putative abrogation impacts of Ajwa seeds on oxidative damage, liver dysfunction and associated complications in rats exposed to carbon tetrachloride.

Industrial toxicants such as Carbon tetrachloride (CCl4) are known to disrupt the oxidative-antioxidative balance, which generates excessive amounts of free radicals leading to chronic or acute liver damage. Natural antioxidants, including Ajwa, play an important role in protecting against hepatotoxicity. This study investigated the prophylactic impacts of ajwa seeds aqueous extract (ASE) against hepatic oxidative injury in rats induced by CCl4. Eighty male Wistar albino rats were equally assigned to eight groups: one group receive no treatment, four groups were received CCl4-olive oil mixture [1:1(v/v)] (0.2ml/100g body weight (bw), intraperitoneally) two times/week for 4 weeks/rat alone or with 200mg Vit. C/kg bw or 5ml ASE/rat or both, and three groups received olive oil, Vit. C, or ASE. Vitamin C and ASE were orally administrated two weeks before CCl4 injection and 4 weeks concomitant with CCl4. Lipid peroxidation, lipogenesis-related genes, hepatic histopathology, Bax immunostaining and DNA fragmentation were assessed. ASE protected hepatic damage by suppressing oxidative stress and elevating activities of antioxidant enzymes, including superoxide dismutase and catalase. ASE also regulated hepatic dyslipidemia, hepatic lipid accumulation and expression of SREBP-1 and FAS genes in CCl4-treated rats. ASE decreased apoptosis through inhibition of CCl4 induced Bax activation in hepatocytes. These observations provide evidence for the hepatoprotective potential of ASE via inhibiting hepatic lipogenesis and oxidative stress, suggesting being used as a natural product in attenuating CCl4 induced oxidative damage, hepatotoxicity and associated dysfunction.

Effect of high-fat high fructose diet and carbon tetrachloride on high sensitivity C reactive protein (hsCRP) levels male Wistar rat

Background: The consumption of a high-fat diet affects fat metabolism in the body, and it gets progressively worse by adding high fructose to the diet. Similarly, the chemical compound carbon tetrachloride (CCl4) can cause toxic effects in multiple organs. High sensitivity C reactive protein (hsCRP) is a micro-inflammatory marker used as a primary preventive tool against several diseases. This study aimed to determine the impact of giving a high-fat, high-fructose diet (HFHFD) and CCl4 on hsCRP levels of Wistar rats.Methods: An experimental study among 24 male Wistar rats aged 8-12 weeks divided into four groups. Rats were fed an HFHFD and were either administered CCl4 biweekly (0.08 mL/kg, peritoneal) or not. The other two groups were fed with standard chow meal with CCl4 injection, and the un-injected group stands as a control group. All groups were monitored for eight weeks, and serum parameters were examined. Data were analyzed using SPSS version 17 for Windows. P-value &lt;0.05 was significant.Results: The intake of a high fat and high-fructose diet for eight weeks was proven to have higher levels of hsCRP than those without the diet. Similar to the administration of 0.8 ml/kg peritoneal CCl4 biweekly shown to have higher levels of hsCRP compared to the control group. This study also showed increased body weight except for the group that received a standard meal and CCl4 peritoneal injection.Conclusion: High-fat high fructose diet and carbon tetrachloride had a significant effect on hsCRP level.

Hepatocyte Mitogen-Activated Protein Kinase Kinase 7 Contributes to Restoration of the Liver Parenchyma Following Injury in Mice.

Background and AimsMitogen‐activated protein kinase kinase (MKK) 7 and MKK4 are upstream activators of c‐Jun NH2‐terminal kinases (JNKs) and have been shown to be required for the early development of the liver. Although it has been suggested that MKK7 might be involved in the regulation of hepatocyte proliferation, the functional role of MKK7 in the liver has remained unclear.Approach and ResultsHere, we examined phenotypic alterations in liver‐specific or hepatocyte/hematopoietic cell–specific MKK7 knockout (KO) mice, which were generated by crossing MKK7LoxP/LoxP with albumin–cyclization recombination (Alb‐Cre) or myxovirus resistance protein 1–Cre mice, respectively. The livers of Alb‐Cre−/+ MKK7LoxP/LoxP mice developed without discernible tissue disorganization. MKK7 KO mice responded normally to liver injuries incurred by partial hepatectomy or injection of CCl4. However, tissue repair following CCl4‐induced injury was delayed in MKK7 KO mice compared with that of control mice. Furthermore, after repeated injections of CCl4 for 8 weeks, the liver in MKK7 KO mice showed intense fibrosis with increased protractive hepatocyte proliferation, suggesting that MKK7 deficiency might affect regenerative responses of hepatocytes in the altered tissue microenvironment. MKK7 KO hepatocytes demonstrated normal proliferative activity when cultured in monolayers. However, MKK7 KO significantly suppressed branching morphogenesis of hepatocyte aggregates within a collagen gel matrix. Microarray analyses revealed that suppression of branching morphogenesis in MKK7 KO hepatocytes was associated with a reduction in mRNA expression of transgelin, glioma pathogenesis related 2, and plasminogen activator urokinase‐type (Plau); and forced expression of these genes in MKK7 KO hepatocytes partially recovered the attenuated morphogenesis. Furthermore, hepatocyte‐specific overexpression of Plau rescued the impaired tissue repair of MKK7 KO mice following CCl4‐induced injury.ConclusionsMKK7 is dispensable for the regenerative proliferation of hepatocytes but plays important roles in repair processes following parenchymal destruction, possibly through modulation of hepatocyte–extracellular matrix interactions.

Indole-3-propionic Acid-aggravated CCl4-induced Liver Fibrosis via the TGF-β1/Smads Signaling Pathway.

Background and AimsThe pathogenesis of liver fibrosis involves liver damage, inflammation, oxidative stress, and intestinal dysfunction. Indole-3-propionic acid (IPA) has been demonstrated to have antioxidant, anti-inflammatory and anticancer activities, and a role in maintaining gut homeostasis. The current study aimed to investigate the role of IPA in carbon tetrachloride (CCl4)-induced liver fibrosis and explore the underlying mechanisms.MethodsThe liver fibrosis model was established in male C57BL/6 mice by intraperitoneal injection of CCl4 twice weekly. IPA intervention was made orally (20 mg/kg daily). The degree of liver injury and fibrosis were assessed by serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and histopathology. Enzyme-linked immunosorbent assay and quantitative real-time polymerase chain reaction (qPCR) were used to detect the inflammatory cytokines. The malondialdehyde (MDA), glutathione, glutathione peroxidase, superoxide dismutase, and catalase were determined via commercial kits. Hepatocyte apoptosis was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. The expression of mRNA and protein was assayed by qPCR, Western blotting, or immunohistochemical staining.ResultsAfter IPA treatment, the ALT and AST, apoptotic cells, and pro-inflammatory factor levels were enhanced significantly. Moreover, IPA intervention up-regulated the expression of collagen I, α-smooth muscle actin, tissue inhibitor of matrix metalloproteinase-1, matrix metalloproteinase-2, transforming growth factor-β1 (TGF-β1), Smad3, and phosphorylated-Smad2/3. Additionally, IPA intervention did not affect the MDA level. Attractively, the administration of IPA remodeled the gut flora structure.ConclusionsIPA aggravated CCl4-induced liver damage and fibrosis by activating HSCs via the TGF-β1/Smads signaling pathway.

Selenium enriched yeast and Gum Arabic combination attenuate oxidative liver damage via suppression of oxidative stress, inhibition of caspase-3 and pro-inflammatory genes expression in carbon tetrachloride-intoxicated rats

In this study we investigated the potential synergistic effects of Gum Arabic (GA) and Selenium enriched yeast (SY) combination on the carbon tetrachloride (CCl4) -caused oxidative damage in the liver of rats. The rats were separated into 5 groups (8 animals per group) and subjected to GA, SY and GA + SY diets following CCl4 injection. The results showed that GA + SY supplementation demonstrated higher protective antioxidative properties than the supplementation of either GA or SY alone, as manifested by lesser activities of serum alkaline phosphatase (ALP), serum transaminase, hepatic malondialdehyde (MDA), and augmented the hepatic activities of superoxide dismutase (SOD), glutathione (GSH) and glutathione peroxidase (GSH-Px) consistent with up-regulation of antioxidant-related genes including glutathione peroxidase 1 (GPX1), superoxide dismutase (SOD1), and heat shock protein 70 (HSP70) in CCl4-intoxicated rats. Furthermore, GA + SY supplementation revealed mild pathological damage and effectively attenuated expression levels of the proinflammatory genes including interleukin-6 (IL-6), interleukin-1β (IL-1β), and tumor necrosis factor- α (TNF-α). Moreover, GA + SY supplementation alleviated CCl4-induced hepatocytes apoptosis via suppression of caspase-3 expression. We concluded that GA + SY combination displayed strong protective and antioxidative effects against hepatotoxic injury caused by CCl4 in rats via its ability to suppress the oxidative stress, inhibit the caspase-3 and pro-inflammatory genes expression.

Zingiber roseum Rosc. rhizome: A rich source of hepatoprotective polyphenols

Zingiber roseum is native to Bangladesh and widely used in folk medicine. This present study was designed to assess the ameliorative potential of Zingiber roseum rhizome extract in carbon tetrachloride (CCl4) induced hepatotoxicity in mice model. Seven phenolic compounds were identified and quantified by HPLC analysis in the plant extract, including quercetin, myricetin, catechin hydrate, trans-ferulic acid, trans-cinnamic acid, (-) epicatechin, and rosmarinic acid. Hepatotoxicity was induced by administrating a single intraperitoneal injection of CCl4 (10 mL/kg) on 7th day of treatment. The results revealed that plant extract at all doses (100, 200 and 400 mg/kg) significantly reduced (p < 0.05) the elevated serum aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP) concentrations, and these effects were comparable to that of standard drug silymarin. Histopathological examination also revealed the evidence of recovery from CCL4 induced cellular damage when pretreated with Z. roseum rhizome extract. The in-vivo hepatoprotective effects were further investigated by the in-silico study of the aforementioned compounds with liver-protective enzymes such as superoxide dismutase (SOD), peroxiredoxin, and catalase. The strong binding affinities (ranging from −7.3359 to −9.111 KCal/mol) between the phenolic compounds (except trans-cinnamic acid) and oxidative stress enzymes inhibit ROS production during metabolism. The compounds were also found non-toxic in computational prediction, and a series of biological activities like antioxidant, anticarcinogen, cardio-protectant, hepato-protectant have been detected.

Knockout of the Cannabinoid Receptor 2 Gene Promotes Inflammation and Hepatic Stellate Cell Activation by Promoting A20/Nuclear Factor-κB (NF-κB) Expression in Mice with Carbon Tetrachloride-Induced Liver Fibrosis.

BackgroundThis study aimed to investigate the effect of deleting the cannabinoid receptor 2 (CB2) gene on the development of hepatic fibrosis induced by carbon tetrachloride (CCl4) in mice via regulating inflammation.Material/MethodsThe DNA was extracted from the tails of mice to identify whether the cannabinoid receptor 2 gene was successfully knocked out. A liver fibrosis model was established by an intraperitoneal injection of CCl4 into mice. Hepatic damage and hepatic fibrosis were evaluated by detecting serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and staining paraffin sections of liver tissue with hematoxylin-eosin (HE). The secretion and distribution of collagen in liver tissue were observed by Masson staining. Western blot analysis was performed to detect the expression of α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1), tumor necrosis factor alpha-induced protein 3 (A20), phosphorylated nuclear factor-κB p65 (p-NF-κB p65), tumor necrosis factor alpha (TNF-α), and interleukin-6 (IL-6) in liver tissue. Reverse transcription-polymerase chain reaction (RT-PCR) was used to detect the expression of IL-6 and TNF-α mRNA in liver tissue.ResultsCompared with the control mice, the mice with CB2 knockout that were exposed to CCl4 exhibited increased liver damage, liver fibrosis, and upregulated α-SMA, TGF-β1, A20, and p-NF-κB p65 protein levels. IL-6 and TNF-α protein levels and mRNA levels were upregulated.ConclusionsThe deletion of the CB2 gene promoted the activation of hepatic stellate cells in mice with liver fibrosis and aggravated liver fibrosis by up-regulating the protein expression of A20 and p-NF-κB p65 and inducing inflammatory response, potentially providing new insight into the treatment of liver fibrosis.

Inhibitory effect of Xinhui citrus fermentation liquor on liver fibrosis in mice

To investigate the inhibitory effect of Xinhui citrus fermentation liquor on liver fibrosis in mice. Mouse models of liver fibrosis were established by intraperitoneal injection of CCl4 in 105 male C57BL/6 mice, followed by gavage of 0.1 mL 40% CCl4 olive oil 3 times a week (model group, n=49) or daily gavage of citrus liquor at the dose of 0.26 mL (citrus liquor group, n=56) for 8 weeks. Seven mice receiving only olive oil treatment (0.1 mL, 3 times a week) and another 7 treated with citrus liquor served as the control group. Liver tissues and serum samples were collected from 7 mice in the citrus liquor group and model group each week and from the mice in the two control groups at the 8th week for pathological examination of the liver tissues using HE staining and Sirius red staining and for determination of the biochemical indexes of liver function. The mice in the model group showed progressively worsened liver fibrosis with obvious hepatic steatosis, necrosis and inflammatory cell infiltration. These liver pathologies were much ameliorated in citrus liquor group, which showed significantly reduced vacuolation, inflammatory cell infiltration, collagen deposition and the Ishak score of the liver tissue (P < 0.05). Serum levels of cholyglycine, alanine aminotransferase, transglutaminase and alanine aminotransferase were all significantly lower in citrus liquor group than in the model group (P < 0.05). Xinhui citrus fermentation liquor has protective effect on the liver and can significantly ameliorate liver fibrosis in mice.

Astilbin Protects Against Carbon Tetrachloride-Induced Liver Fibrosis in Rats

Background: Hepatic fibrosis is an inflammatory liver disease, and there is no effective therapy at present. Astilbin is a bioactive ingredient found in many medicinal and food plants, with antioxidative, anti-inflammatory, and antitumor properties. Objectives: This study aimed to investigate the protective effect and related molecular mechanism of astilbin against carbon tetrachloride (CCl4)-induced liver fibrosis in rats. Methods: Liver fibrosis was induced by injection of CCl4 in male Sprague-Dawley rats, and those rats were then treated with astilbin at different concentrations. Pathological changes, collagen production, inflammatory cytokine, and oxidative stress were evaluated to evaluate the effects of astilbin on CCl4-induced hepatic fibrosis. Real-time PCR and western blot were performed to detect the mRNA and protein expression of indicated genes. Results: We discovered that CCl4 caused significant fibrosis damage in rat liver, and astilbin dose-dependently improved the liver functions and fibrosis degree. Astilbin treatment significantly decreased collagen production, inflammatory response, and oxidative stress in vivo. Mechanically, administration of astilbin obviously elevated the hepatic levels of Nrf2 and its downstream components, including NAD(P)H:quinone oxidoreductase 1 (Nqo1), heme oxygenase (HO-1), glutamate-cysteine ligase catalytic subunit, and glutamate cysteine ligase modifier. Conclusions: Taken together, these findings demonstrate that astilbin could protect against CCL4 induced-liver fibrosis in rats.

Protective role of protocatechuic acid in carbon tetrachloride-induced oxidative stress via modulation of proinflammatory cytokines levels in brain and liver of Wistar rats.

Protocatechuic acid (PCA) possesses numerous pharmacological activities, including antioxidative and anti-inflammatory activities. This study seeks to investigate its underlying mechanism of action in the liver and brain toxicity induced by CCl4 in male albino rats. Rats were given PCA at 10 and 20mg/kg daily and orally as a pretreatment for seven days. A single injection of CCl4 was given 2h later to induce brain and liver toxicity. CCl4 moderately elevated the activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). PCA lowered AST level significantly when compared to control. Total protein and albumin levels presented insignificant changes (p>0.05) in all groups while lipid profile showed increased total cholesterol level and reduced high-density lipoprotein (HDL) by CCl4. PCA (10mg/kg) significantly reduced the cholesterol level while the 20mg/kg dose moderately prevented HDL reduction. There was an increased MDA production with a corresponding low GSH level in the group treated with CCl4. Activities of superoxide dismutase, catalase, and glutathione-S-transferase in both organs also declined. PCA, especially at 10mg/kg attenuated lipid peroxidation by increasing GSH level in the organs. Biochemical assays revealed the improvement of antioxidant enzyme activities by PCA in these organs. Furthermore, PCA lowered the level of proinflammatory cytokine COX 2 in the brain and liver while NF-kB expression was inhibited in the brain. Histopathology reports validated the effects of PCA. PCA exhibited protection against toxicity in these tissues through antioxidant and anti-inflammatory activities and the potential mechanism might be through modulation of the NF-κB/COX-2 pathway.

Disturbances in Thyroid Hormone Metabolism in Rats Exposed to γ- Radiation and Carbon Tetrachloride: The Role of N- acetyl cysteine and Sodium Selenite

THIS work aims at detecting the disturbances in thyroid hormone metabolism in male rats exposed to liver injury by γ- radiation and/or carbon tetrachloride (CCl4), in addition to investigating the modulatory role of N-acetyl cysteine (NAC) and sodium selenite (Se) supplementation. Subcutaneous injection of CCl4 twice a week for 8 weeks and/or whole-body irradiation (6 Gy, single dose) one day after the last dose of CCl4 induced hepatotoxicity as manifested by elevation of serum alanine aminotransferase and gamma-glutamyl transferase and oxidative stress in liver tissue. Moreover, significant increases were recorded in pro-inflammatory markers: nuclear factor kappa B and interleukin- 1beta levels. This was also accompanied by a significant decrease in the activity of type 1 iodothyronine deiodinase in the hepatic tissue and triiodothyronine and thyroxin levels in serum, while thyroid-stimulating hormone showed a non-significant increase. Histological examination of liver sections showed marked alterations. However, oral supplementation of NAC and Se for 2 weeks after exposure to CCl4 and/or γ- radiation attenuated the changes induced by these toxins. In conclusion, supplementation of NAC & Se may be useful to attenuate thyroid hormone metabolic disturbances associated with liver injury induced by chemical and physical environmental toxins.

Arctigenin attenuates CCl4-induced hepatotoxicity through suppressing matrix metalloproteinase-2 and oxidative stress

BackgroundIn spite of the huge advances in recent medicine, there is no effective drug that completely protects the liver from toxic materials. This study was conducted to investigate the hepatoprotective effect of arctigenin from burdock (Arctium lappa) against carbon tetrachloride (CCl4)-induced liver injury.ResultsArctigenin pre-administration reduced hepatotoxicity markers significantly as compared to CCl4 group. In addition, both silymarin and arctigenin declined matrix metalloproteinase-2 (MMP-2) in the serum (1177 ± 176), (978 ± 135) significantly as compared to CCl4 group (1734 ± 294). The hepatic antioxidant parameters (total glutathione, superoxide dismutase, and glutathione reductase) were significantly decreased after CCl4 injection, an effect that has been prevented by pre-administration of both silymarin and arctigenin. Histological examinations illustrated that arctigenin reduced CCl4 damage, where it decreased inflammation, congestion, and ballooning.ConclusionsArctigenin exerted a hepatoprotective effect against CCl4-induced liver damage in terms of suppressing MMP-2 and oxidative stress comparative to that of silymarin.